Contra Costa County, CA Building Safety: Smoke Alarms (2026)

Smoke alarm requirements in Contra Costa County derive from California Health & Safety Code 13113.7 and 13113.8, plus the California Residential Code (CRC R314) and Fire Code (CFC 907). Every dwelling unit, whether single-family, duplex, apartment, condominium, or manufactured home, must have smoke alarms installed inside each sleeping room, outside each separate sleeping area in the immediate vicinity of bedrooms, and on every level of the dwelling including basements. Alarms must be interconnected in new construction and substantial remodels so that activation of one sounds all alarms. Since July 1, 2015, any battery-only smoke alarm sold or installed in California must be a 10-year sealed non-replaceable battery model bearing the California State Fire Marshal listing; replaceable 9V batteries are no longer acceptable for new installations. Hardwired alarms with battery backup remain standard in new construction. Sellers of residential property must certify smoke alarm compliance at sale. Landlords are responsible for installation and maintenance in rental units, though tenants must notify of defects. Failure to maintain working smoke alarms is a violation that can be enforced through code enforcement and carries liability exposure under fire-loss litigation. The Contra Costa Fire Protection Districts provide installation assistance and education.